Wide-field common-path incoherent correlation microscopy with a perfect overlapping of interfering beams

Abstract

Incoherent correlation microscopy is recently discovered technique for digital imaging of three-dimensional objects in a quasimonochromatic spatially incoherent light. Its operation is based on wavefront division carried out by a spatial light modulator and capturing correlation recordings of the observed scene. To achieve image reconstruction, at least a partial overlapping of the signal and reference waves created by the spatial light modulator is necessary. In the known experimental configurations, the overlapping of interfering beams is strongly reduced in off-axis areas of the object and the image can be reconstructed only in a very small portion of the field of view provided by the used microscope objective lens. Here, we propose and successfully demonstrate modified experimental system working with two-component relay optics inserted between the microscope objective and the spatial light modulator and providing full overlapping of correlated beams in all areas of the field of view of the objective lens. The benefits and applicability of the proposed system design are clearly demonstrated on the imaging of the USAF resolution targets.

CINCH (confocal incoherent correlation holography) super resolution fluorescence microscopy based upon FINCH (Fresnel incoherent correlation holography)

“…In turn, we positioned the entry tube lens (Nikon, 200 mm effective focal length) with its own front focal plane at the back plane of the objective. The GRIN/glass lens combination that creates the hologram is located at the back focal plane of L2 and thus the confocal head takes the place of the 4f relay reported before 14,16 . As shown in Figure 1, the confocal unit received the excitation light from the lamp (Photofluor II illuminator, 89 North) and reflected it off a dichroic mirror in a microscope filter cube and then projected it through a Nipkow disk.…”

Improved axial resolution of FINCH fluorescence microscopy when combined with spinning disk confocal microscopy

“…In turn, we positioned the entry tube lens with its own front focal plane at the back plane of the objective. The GRIN/glass lens combination that creates the hologram is located at the back focal plane of L2 and thus the confocal head takes the place of the 4f relay reported before [10,12]. As shown in Fig.…”

“…Self-referenced holographic techniques [1][2][3][4][5] such as FINCH [1,[3][4][5][6][7][8][9][10][11][12] offer advantages over standard coherent holographic techniques, including the lack or requirement for use of a laser in the recording process, suitability for any illumination technique, and, for FINCH and similar techniques, inherent super-resolving capability for objects located away from the focal plane of the entry lens into the system. Thus, since the FINCH concept provides a platform for flexible and adaptable methods with the ability to offer high resolution 3D fluorescent images with little additional difficulty beyond standard imaging techniques, they are increasingly studied as techniques for improving microscopy performance.…”

Three-Dimensional Imaging by Self-Reference Single-Channel Digital Incoherent Holography

“…A noteworthy FINCH-related technique is the self-interference incoherent digital holography (SIDH), in which the SLM-aided single channel of FINCH is replaced by a modified Michelson interferometer with two mirrors of different spherical curvatures [51]–[53]. Another interesting design in this context is a FINCH-like system with a wide field-of-view that is achieved using an optical relay system placed between two main components of FINCH: the objective lens and the SLM [54]. Other examples of FINCH-based imagers include the synthetic aperture with Fresnel elements (SAFE) systems [55]–[57].…”